private void btn_flash_boot_Click(object sender, EventArgs e)
        {
            String source_path = txt_boot.Text;


            if (File.Exists(source_path))
            {

                System.IO.File.Copy(source_path, "boot_AndroidControl.img", true);

                //---Reboot in Bootloader
                StripStatus.Text = "rebooting bootloader...";

                System.Diagnostics.ProcessStartInfo psi =
                new System.Diagnostics.ProcessStartInfo("C:/adb.exe", "reboot-bootloader");
                psi.WindowStyle = System.Diagnostics.ProcessWindowStyle.Hidden;
                System.Diagnostics.Process.Start(psi).WaitForExit();


                // Checkt ob Gerät in Fastboot ist
                bool in_fastboot = false;
                while (in_fastboot == false)
                {

                    Process process = new Process();

                    process.StartInfo.UseShellExecute = false;
                    process.StartInfo.RedirectStandardOutput = true;
                    process.StartInfo.RedirectStandardError = true;
                    process.StartInfo.CreateNoWindow = true;
                    process.StartInfo.UseShellExecute = false;


                    System.Threading.Thread.Sleep(500);

                    process.StartInfo.FileName = "C:/fastboot.exe ";
                    process.StartInfo.Arguments = "devices";

                    process.Start();

                    string output = process.StandardOutput.ReadToEnd();

                    if (output.Contains("fastboot"))
                    {
                        in_fastboot = true;
                    }
                    else { in_fastboot = false; }

                }


                StripStatus.Text = "flashing boot...";

                System.Threading.Thread.Sleep(1500);

                System.Diagnostics.ProcessStartInfo psi2 =
                new System.Diagnostics.ProcessStartInfo("C:/fastboot.exe", "flash boot boot_AndroidControl.img");
                psi2.WindowStyle = System.Diagnostics.ProcessWindowStyle.Hidden;
                System.Diagnostics.Process.Start(psi2).WaitForExit();

                System.Threading.Thread.Sleep(1500);

                StripStatus.Text = "boot flashed, rebooting phone now...";
                System.Diagnostics.ProcessStartInfo psi4 =
                new System.Diagnostics.ProcessStartInfo("C:/fastboot.exe", "reboot");
                psi4.WindowStyle = System.Diagnostics.ProcessWindowStyle.Hidden;
                System.Diagnostics.Process.Start(psi4).WaitForExit();

                System.IO.File.Delete("boot_AndroidControl.img");
                System.Threading.Thread.Sleep(2500);
                StripStatus.Text = "Bereit";


            }

              else {
                  MessageBox.Show("can't find recovery.img");
              }

        }